| From 14be1689c96842bd93cbcda4cb0bd4c5cc15a5a0 Mon Sep 17 00:00:00 2001 |
| From: Hugh Dickins <hugh@veritas.com> |
| Date: Thu, 16 Apr 2009 21:45:05 +0000 |
| Subject: mm: pass correct mm when growing stack |
| |
| From: Hugh Dickins <hugh@veritas.com> |
| |
| upstream commit: 05fa199d45c54a9bda7aa3ae6537253d6f097aa9 |
| |
| Tetsuo Handa reports seeing the WARN_ON(current->mm == NULL) in |
| security_vm_enough_memory(), when do_execve() is touching the |
| target mm's stack, to set up its args and environment. |
| |
| Yes, a UMH_NO_WAIT or UMH_WAIT_PROC call_usermodehelper() spawns |
| an mm-less kernel thread to do the exec. And in any case, that |
| vm_enough_memory check when growing stack ought to be done on the |
| target mm, not on the execer's mm (though apart from the warning, |
| it only makes a slight tweak to OVERCOMMIT_NEVER behaviour). |
| |
| Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> |
| Signed-off-by: Hugh Dickins <hugh@veritas.com> |
| Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
| Signed-off-by: Chris Wright <chrisw@sous-sol.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| --- |
| mm/mmap.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/mm/mmap.c |
| +++ b/mm/mmap.c |
| @@ -1580,7 +1580,7 @@ static int acct_stack_growth(struct vm_a |
| * Overcommit.. This must be the final test, as it will |
| * update security statistics. |
| */ |
| - if (security_vm_enough_memory(grow)) |
| + if (security_vm_enough_memory_mm(mm, grow)) |
| return -ENOMEM; |
| |
| /* Ok, everything looks good - let it rip */ |
